I'm assuming that you are the same person who opened the JIRA ticket NIFI-7114. While we welcome your question, and you may get an answer from someone in the community, you might want to wait until an Apache committer responds to your JIRA ticket. There might be a simple solution.
Bill Brooks, Community Moderator Was your question answered? Make sure to mark the answer as the accepted solution. If you find a reply useful, say thanks by clicking on the thumbs up button.
While I believe the issue to be a bug that would mean being locked in 1.8 for months until a version with the correction is published. So I hope that someone has found some kind of work around that would allow me to upgrade.